he puzzle about the ancestral function of toll-receptors has been solved. For more than 25 years, researchers from medicine and biology have been studying toll-receptors, revealing functions in immune defence on the one hand and developmental biology on the other. A research team from Kiel University (Germany) is now reporting that toll-receptors have primarily served to identify germs and to control bacterial colonisation of organisms – typical immune defence functions. The study was now published online in the Proceedings of the National Academy of Sciences (PNAS) and has implications for human medical research.